First off, I'd like to thank everyone for making this site possible, it is a wealth of knowledge. Unfortunately there are about a billion pages of it to search through. so I'd like to start this thread about my bike, and all questions or comments pertaining to it.  She's a 2003 LS 650, jardine exhaust, k&n cone filter, #55 pilot w/bh - #155 main, and some other strange modifications I'm not familiar with.
At the moment I'm trippin on this whole jetting/mixture screw/powerband/flames shooting out the tailpipe issue. I'm one full turn out on the mixture screw and there is one really thin metal washer atop the needle. this bike pops and cracks and backfires and shoots flames 'n stuff. also there is like this dead spot in the power band. how do I go about fixing this stuff?

Gotcha,, good idea. i know i read the topic somewhere on this site as to the what the stock settings are because I'm not sure this bike has ever been at stock settings. though I will say the pilot jet was a #47 and the main jet was probably stock. what was happening was the bike will go on the freeway for about a mile and then start starving for gas because the main jet wasnt supplying enough. I was going off of Diamond Jims LS650 progressive jetting guide and just jumped from like stage 1 to stage 7. possibly I just keep the 155 Main and lower the pilot. hey when you're going like 80 on the freeway does gas squirt of both the pilot and the main at full force? Like, does it take both of them to meet the fuel need at freeway speed?

I ran a 155 over 55 for many years on the west coast. You shouldn't be having any backfiring or popping. If you are at sea level to about 700 feet in elevation, your carb is probably a tad rich, my bike smoked like an old diesel big rig, pilot was too big. No messing with the white spacer or washer conversions, I don't pull vacuum slides out until they fail.

Stock on mine (1998) was a 47 pilot jet and I think a 150 main. Switching it back to a 155 over 50 to cut the smoke. Which is actually just toasted yet unburnt fuel.

Boogieman wrote on 04/28/13 at 00:53:16:

This is what I'm taking about with the large over-laps.

http://www.sudco.com/Carburetor/MikuniThrottleChart.700.jpg

Wow thanx everyone for being so willing to help.
Ok LANCER, so as far as strange modifications go I'm really just talking about tank, handle bars, seat, signals and stuff. I got this bike from my brother and he's the one that basically made it rideable by attaching all that stuff temporarily and got it running. He did the LED/diamond plate stuff. Im posting some pics to give everyone a better idea of what I'm dealing with here. The tank doesnt fit it very well So either I get a new tank or move/remove all that nonsense from underneath it. yeah I don't know what all that stuff is underneath there but needs to be taken off completely or relocated.
 I took the carburetor halfway apart (top half) and clean it up all nice. As it turns out, I had not even one washer atop that little washer-clip thing. so I put that big washer back in there, resembled it, tuned it a little (she does respond to 1/4 turns) and went to the hardware store to get the #4 washers. there's a huge difference between not having any washers in there and having that big washer there. still pops and pings when closing the throttle, one or two pops between gears but not all everytime, slightly less of a backfire on shutdown, but noticeably more power/pull. i dont know what kinda petcock this is but it needs no vacuum attchmnt. perhaps i should get a raptor petck.

petcock

needle